Strut drive (submerged prop) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/strut-drive/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
Catalog version: 2026-10-20

Sizes: see table below
- A strut holds the propeller shaft behind the transom; its angle and depth set how the prop lifts or pushes down the stern. Manufacturers usually recommend 0 deg; 0.030 in of shim under a 1.75 in strut adds 1 deg (Model Gas Boats).
- Racers keep the shaft centreline 3/8-1/2 in above the keel with the strut flat or slightly negative, and offset the drive to starboard to counter torque roll (Model Gas Boats forum).
- The file is a reference example built by Xem Studio from the numbers above (44 mm RC prop (SV Design).). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

parameter  value or range  source
Default strut angle  0 deg  Model Gas Boats
Shim per deg (1.75 in strut)  0.030 in  Model Gas Boats
Shaft height  3/8-1/2 in above keel  Model Gas Boats forum
Offset to starboard  1/4-3/8 in (mono)  Model Gas Boats forum
Stock RC shaft angle  about -6 deg  SV Design (Stealthwake)

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Model Gas Boats: Some tips on setting up a hydroplane hull — web — Publisher's page; dimensions are facts — https://modelgasboats.com/magazine/tech-articles-mainmenu-608/369-hydro-setup-tips
- Model Gas Boats forum: Stinger drive versus strut support set up — web — Publisher's page; dimensions are facts — https://modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/16025-stinger-drive-versus-strut-support-set-up?start=0
- Model Gas Boats forum: Need help setting up a mono for the first time — web — Publisher's page; dimensions are facts — https://www.modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/21138-need-help-setting-up-a-mono-for-the-first-time
- SV Design: Pro Boat Stealthwake upgrades info (Feb 2022) — web — Publisher's page; dimensions are facts — https://myplace.frontier.com/~sv_design/Pro%20Boat%20Stealthwakes%20Upgrades%20Info%20SVC_Feb-2022.pdf

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/strut-drive/index.json
API: https://xemstudio.com/api/geometry?object=strut-drive